THE HAGUE, Netherlands — An international investigation into the Malaysia Airlines Flight 17 disaster is officially looking into a scenario that the plane was downed by a missile fired from conflict-ridden eastern Ukraine.

A Dutch judicial statement said Monday the international investigating team is looking for witnesses "that can tell more about the transport, crew and firing of a Buk missile system in the Donbass region."

The cause of the MH17 disaster last summer is a subject of major diplomatic disputes. Ukraine and Western governments say Russia-backed separatist fighters are responsible for downing the plane, while Russian state-run television has claimed Ukraine's air force was to blame. All 298 people aboard the Boeing 777 flying from Amsterdam to Kuala Lumpur were killed.